The appliance of science

Brining seems a rather old-fashioned technique, but we've been using it recently to improve the flavour of several dishes - not on the traditional ham or bacon, but on lamb before it goes into Lancashire hot pot and on rabbit for rabbit terrine.

Brining just means immersing a piece of meat, poultry or fish in a saline solution. You may think that the protein will end up like ham, and I suppose that would happen if the salinity was high enough and you brined the meat for long enough. But that's not the case if you use a 5% solution (around 5g salt to 100ml water) and are careful about how long you brine it. The brine penetrates the meat through osmotic pressure. The sodium and chloride in the salt disrupt the muscle filaments, drawing out water and leaving salt in. This then goes to work on the proteins, with the result that the muscle cells can hold more water infused with the salt and other flavourings (herbs or spices) in the brine.

The length of time you brine meat depends on its size: the larger the cut, the longer the brine will need to work its magic (it may take two days for big joints). It is crucial that you wash off the brine afterwards, or the meat will be very salty and will continue curing. Brining has the side-effect, too, of slowing down enzyme activity, so helping preserve the meat and making it hard for bacteria to grow.

When you cook the meat, it will still lose moisture but, because the brining has increased its water retention, it will be more moist than it would otherwise be.